The glacial and glacio-marine sediments of the Oligocene Polonez Cove and Early Miocene Cape Melville Formations on King George Island (South Shetland Islands, West Antarctica) yield numerous erratic boulders of limestone, in particular archaeocyathan-algal boundstone, oolite, onkolite, and biomicrite. Some of these boulders are fossiliferous and contain archaeocyathans, sponges, inarticulate brachiopods, monoplacophorans, gastropods, hyolithids, trilobites, ostracodes and such enigmatic fossils as: Chancelloria, Coleolella. Dailyatia. Halkieria. Hadimopanella. Hyolithellus. "Lenastella", Mongolitubulus and Torellella. The small shelly fauna appears to be Early Cambrian (Botomian) in age. The boulders of fossiliferous limestones resemble the rocks of the Shackleton Limestone unit in the central Transantarctic Mts. The lithological composition of the boulder assemblage brought to King George Island during the Tertiary glaciations suggests that the Cambrian outcrops around the Weddell Sea are the source of the erratics. The Antarctic Lower Cambrian fauna resembles its analogues in Australia and Asia.
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